The most dangerous criminals should be sentenced to life with no possibility for parole, the Liberal Democrats have said.
Under plans launched by the party today, there would also be no automatic right to early release - the parole board would have discretion to say if an offender was still dangerous.
The Lib Dems also proposed an end to the automatic 30 per cent reduction in an offender's sentence if they plead guilty - they believe the judge should decide.
Today's proposals come amid mounting concern about sentencing, after Craig Sweeney was given a minimum of five years for sexually abusing a three-year-old girl. It was then revealed that 50 people given life sentences since 2000 were already out of jail.
Home secretary John Reid condemned the Sweeney sentence as "unjustly lenient" and the attorney general reviewed it to see whether this was the case. He found, however, that the judge in question had simply followed the guidelines set out by the government.
The Criminal Justice Act 2003 allows most prisoners to leave prison after serving half their sentence, meaning that someone given ten years could leave after just five. However, they would be on license and could be recalled to jail.
In a speech to judges last night, the lord chancellor said sentencing was at the heart of people's perception of the criminal justice system, and noted that any attempt by politicians to interfere "must be resisted".
More importantly, Lord Falconer warned against dividing the arguments into harsh custodial sentences and community penalties, saying: "It is obvious that more judicial discretion is required."
The Liberal Democrats claim their proposals would create a simpler system, in which judges have more say and which the public could understand.
The most serious offences would result in life custody with no parole, while criminals in the next categories would be given an indefinite sentence with a minimum term, and would only be released after the judge responsible for the case and the parole board agreed.
Fixed term sentences would be handed out to all other serious offenders, with the maximum and minimum terms announced by the judge in court. Non-violent criminals, such as shoplifters, would be given community work as an alternative to jail.
"Our proposals mean that sentences will do exactly what they say on the tin. For too long the government has been talking tough on crime while second guessing the judges. The public has been left utterly confused," said home affairs spokesman Nick Clegg.
"This is a balanced package which would ensure the most dangerous criminals do their time in prison, whilst finding new ways to deal with lesser offenders."